Talk:Head-up display

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[edit] Focusing in cars

"while in automobiles the display is generally focused around the distance to the bumper.". Does anybody have a source for that? Or could someone explaing why manufacturers would want you to focus that close. I just tried looking out my window, and there's significant loss of focus on the ~20 m background when I focus on the ~3 m window, so it doesn't seem right to place the HUD so close. 85.224.198.207 (talk) 16:40, 13 December 2007 (UTC)

Dumb assumption: in order not to distract the eye from anything on the street. A fuzzy head-up projection is less likely to obscure something on the road.
Another problem (not mentioned in the article) with HUDs in cars is that of non-uniform backgroud brightness. A car driver may simultaneously face very dark and bright area. Like, very bright sky above and a dark tunnel ahead. Either the HUD adjusts to the sky, outshining the dark tunnel interior, or it adjusts to the tunnel, becoming so dim that the driver cannot read the speed anymore. Ot the HUD may be partially over bright and dark background, making the reading error-prone. In aircraft, this is less of a problem, since the background is more uniform. And speed-traps, curves, tunnels and pedestrains are also typically less of issue there. ;-)
Sorry, I have no sources for my information; I investiagted this stuff like 15+ years ago. --80.134.46.77 (talk) 13:44, 19 May 2008 (UTC)

[edit] Example Images

They're not great, esp not the last one. Anyone have better ones? --jazzle 02:59, 2 October 2006 (UTC)

You can lift a couple off my web site if you like. However, they're also not that good. I'll leave the decision up to you. http://www.richardfisher.com/design_examples.htm

I'm assuming you mean the one with symthetic vision? Click on it and get the larger version it's actually pretty good (but not ideal for an entry level discussion.) The optical path for civilian HUDS is way different from military ones. For example field of view is greater, projector is overhead and not below, as well as a curved combiner rather than flat glass. Getting all of this into a package a few inches think over the pilots head is a reall challange. Brian (ZazenCID)

[edit] Head-up display != Heads up display?

Am I the only one who distinguishes between a head-up display (a display viewable without looking down) and a heads up display (a display which displays warning indications, i.e. gives you a 'heads up')?tim 13:12, 29 January 2007 (UTC)

Your distinction is also one used within the supplier community. It's either "fly with your head up!" or "Heads up you didn't lower the gear!"  :)> Brian

[edit] Down and Out in the Magic Kingdom Deletion

I deleted this reference from Experimental Uses. It seemed off hand and slightly irrelevant, but if anyone can show otherwise, it should go back in. It didn't seem to fit with the most of the other part of the article.John Pouliot 02:14, 16 February 2007 (UTC)

[edit] Commercially Available HUDs

I created this section from links previously in the External Links section, to indentify them as Consumer products, not necessarily unbiased informational material. I know advertising is not at all appropriate for wikipedia, but these websites are also a treasure trove of information concerning HUD technology. Is there an offical opinion on this? John Pouliot 02:14, 16 February 2007 (UTC)

[edit] Copyedit

This article, or a portion of it, was copyedited by the League of Copyeditors in February 2007. If you would like to participate, please visit the project page, where you can join the project and see a list of open tasks.
  • Copyeditor(s): John Pouliot 02:14, 16 February 2007 (UTC)
  • Proofreader: Galena11 18:52, 20 February 2007 (UTC)

[edit] Civil Aircraft Applications Discussion

I moved the technical elements of OPU discussion to the Display section, and am copyediting and wikifying Civil Aircraft Applications so far. Could ZazenCID just review these changes for accuracy? Thanks John Pouliot 02:56, 5 March 2007 (UTC)

I removed this section:

Since being introduced on HUDs, both the FPV and acceleration symbols are becoming standard on head-down displays (HDD). The actual form of the FPV symbol on a HDD is not standarized but is usually a simple aircraft drawing, such as a circle with two short angled lines, (180 ± 30 degrees) and "wings" on the ends of the descending line. Putting one of these angle lines on the horizon allows the pilot to easily fly a coordinated 30 degree turn while maintaining altitude.

because I didn't feel that it greatly contributed to HUD tech. Would it be appropriate elsewhere? John Pouliot 03:29, 5 March 2007 (UTC)

Moving OPU to Display section. In a military HUD the projector is part of the combiner assembly. An OPU is only present in civil HUDs (and military transports) and not in tactical aircraft (where there is no overhead, only canopy) :)> Also the section is trying to discuss the HUD as a system with a few words about each of the major elements of the system. I disagree with this move. ..................................................... Removed Section - Well you can take it out, however it is a critical element of commercial HUDs. You might consider removing the first line (migration to HDD) however the discussion on the FPV itself really needs to remain. - Brian (ZazenCID)

[edit] Update 3/5/07

Ok, I added the tactical aircraft note into the display section.

I also re-added the HDD FPV symbol information, you're completely right.

"Also the section is trying to discuss the HUD as a system with a few words about each of the major elements of the system. I disagree with this move."

What do you mean by this?

- John - John Pouliot 02:06, 6 March 2007 (UTC)

Update: Copyedited the SVS section. Truly Fascinating! John Pouliot 02:27, 6 March 2007 (UTC)

I went back are read it and it reads fine.

I need to add material for Flight Guidance Systems as that appears to be missing from Wikipedia. On the periphery of my knowledge but I've got good stuff from the FAA that I can use as source material.

re SVS. With a side stick controller it's like flying a video game (at least in the simulator never got to fly it for real :( ) The Regulatory folks like to use a term "compelling" for these kinds of displays - that is the computer generated display can become more "real" than what is seen with the eye. One of the real challanges for the design communuity is determining that what is displayed is what is actually in the database. The whole issue of "is the database correct?" generally goes generally unanswered. (This would be a similar problem to the USS San Francisco hitting the top of a mountain while underway at high speed because the charts were not current.) A new radio tower is put up and hasn't found it's way into the charts/database yet. Pilot has a bad case of "get homeitis" tries to do a "direct in" approach because the SVS doesn't show any obstructions in their path and suddenly sees the hazard lights in their flight path. The design community can make systems safe - but only when used as intended. <sigh>

This "compelling display" concern hindered the introduction of moving map displays as there was a often expressed concern by the regulatory authorities that the pilot would go "head down" and simply fly the airplane along the route shown on the map. (IFR usually means Instrument Flight Rules but in this case would mean "I follow the Roads.") ZazenCID 22:20, 12 March 2007 (UTC)

[edit] re

Adding the Flight Guidance Systems info would be great. This article seems to be exponentially expanding. Awesome. I'm almost tempted to nominate it for Good Article status...hmmm

As for the SVS. Have there been any media-covered accidents because of its mis-use? John Pouliot 02:10, 13 March 2007 (UTC)

Sorry John - haven't been keeping up :) SVS is not approved - as yet. There are great concerns about the pilot flying SVS and not bothering to look out the window (new systems will be able to present the SVS display on either the head-up or head-down display. There is a focus on providing this as "guidance" so that IF the crew needs to deviate from a normal and approved flight path then stuff in the flight path could be brought to the crews attention before TAWS (terrain alerting and warning system - note that TAWS is related to Honeywell patents which the vigrously defend - but sometimes loose [1] It should be noted that SVS will be an external system to both HUD and HDD with these systems "just displaying the video stream." This makes life a bit easier for those of us doing "just displays" :)> Brian (ZazenCID 22:28, 31 May 2007 (UTC))

[edit] Rockwell Collins Link

I linked directly to a Collins web site. Brian — (ZazenCID 14:43, 11 June 2007 (UTC))

[edit] Update to SVS section

Added information in the SVS section related to usage of the image (actually restrictions on the use) Also added a brief note about safety analysis in one of the foot notes. Added Max-Viz and CMC to IR camera suppliers. Moved Kollsman to Commercial sites along with the new links to Max-Viz and CMC. ZazenCID 20:24, 13 April 2007 (UTC)

[edit] Removed ===Additional Applications===

  • FLIR - Forward Looking InfraRed.
  • Using HUD for assisting in the avodiance of runway incursions.
  • The HUD designers are also working with NASA to certify a synthetic vision system, using GPS for similar terrain

Observation and scanning of the approach course for immediate obstacles in unfamiliar locations.

This was removed 5/31/07

- FLIR is the name of FLIR Systems and not used as a generic term. Also see "Enhanced Vision" earlier.

- Using HUD for taxiway guidance is an unapproved use of the system if runway visibility criteria is not met without EVS.

- The HUD is capable of showing runway edges for low visibility landings and takeoffs, however taxi way symbology would require a rule change by the regulatory agencies.

- The discussion on HUD designers also working with NASA is a duplicate of the Synthetic Vision part of this page. -Brian- (ZazenCID 22:19, 31 May 2007 (UTC))

[edit] Automotive section correction

List of automakers that utilize Head-Up displays was corrected and rearranged in the correct alphabetical order.

76.188.158.228 (talk) 14:48, 12 April 2008 (UTC)